[GRASSLIST:5873] Re: Looking for Advice on Buffering

[Radim Blazek]

Nathan Wales wrote:
> I have been working with Grass 6.0 to try to output elevation values from a 
> raster map at specific intervals from coordinates. I have been sucessful at 
> getting coordinates into Grass. However, I have not found a way to create 
> buffers or concentric circles that overlap and maintain the centroid 
> attribute. I want to have the circles in miles (like in the raster buffer) 
> rather than map units (like in the vector buffer). I am willing to try to 
> write code for a solution, but I have limited experience. 
> 
> Does anyone have a suggestion for how I should approach this task?
> 
> Thanks for taking the time to read this message, and for briefly thinking 
> about it. 
> 
> Cheers,
> Nathan 

You have to overlay individual buffers in loop, for example:

v.in.ascii -e output=buffers

for C in 1 2 3
do
     v.extract input=points output=point list=$C
     v.buffer input=point output=buffer
     v.overlay -t ainput=buffers binput=buffer \
                  output=tmp olayer=0,1,1
     g.copy vect=tmp,buffers
done

Radim